Circuit-breaker system.



W. M. SCOTT. CIRCUIT BREAKER SYSTEM.

APPLICATION FILED 0OT.11, 1909. 1,031,205. Patented July 2, 1912.

2 SHBETSSHEET 1.

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CIRCUIT BREAKER SYSTEM.

APPLICATION FILED 001211, 1909. 1 ,03 1,205. v Patented July 2, 912.

2 SHEETSSHELET 2.

UNITED STATES PATENT OFFICE.

WILLIAM E. SCOTT, OF PHILADELPHIA, PENNSYLVANIA, ASSIGNOR TO THE CUTTERELECTRICAL AND MANUFACTURING CQMIPANY, A, QQRPORATION OF NEW JERSEY.

CIRCUIT-BREAKER SYSTEM.

Specificatiompf Iietters Patent.

Patented July 2,1912.

Original application filed- January 19, 1907, Serial No. 353,047.Dividedand this application filed October 11, 1909. Serial No. 521,985.,

To all whom-'t't-inay concern:

Be vit known that 1, WILLIAM M. SCOTT, a citizen of the United States,residing in the city of Philadelphia, county of Phila- 5 delphia, andState of Pennsylvania, have invented a new and useful Circuit-BreakerSystem, of which the. following is a specification. 1

My invention relates to a system of proto tection for interrelatedelectric circuits, such, for example, as a three or more wire system inwhich the voltage between outside wires or conductors is greater thanthe voltage between either of the outside conl5 ductors'and any of theintermediate conductors.

My invention residesin such an electric protective system comprising a.three or more Wire system and a plurality of circuit breakers, any oneor all of which is or are provided with tripping means responsive topotential .changes on the system, so that any or all of, the circuitbreakers will be tripped when the potential between any 35 given pair ofconductors of the system changes throngh a considerable range and thetrippingmechanisms of the several circuit breakers maybe mechanically.interconnected so that upon the operation of any 30 one trippingmechanism all the tripping mechanisms are operated, so that all thebreakers open.

Myfnvention resides also in the features herelnafter described ahdpointed out in 55 the claims.

For an illustration of one of the forms my invention maytake, referenceis to be had to the accompanying drawing, in

which:

LO' Figured is a side elevation'of an automatic circuit breaker havingtripping coils suiting it for my protective system. Fig. 2 isadiagrammatic view of circuit arrangements of my protective system asapplied to a three Wire system. Flg. 3 is a front ele-' vational'viewshowing two automatic circuit breakers, eajch' provided with trippingmeans such as shown in Figs. 1 and 2, and

having their tripping mechanisms mechani- 0 why interconnected.

In .Fig. 1 there is shown an automatic circuit breaker in which'thetripping mech 'anism is of a type suiting it to my invention. It is tobe understood, however, that clearness.

any other type of circuit breaker may be employed in my system and thatmy invention isnot limited to the construction of the circuit breaker.Upon a base 1, of any suitable insulating materiahsuch as marble, aresecured the main terminal blocks 2 and 3 held by studs 4, 4 and nuts 5,5. A movable laminated bridging member 6 is adapted to engage the mainterminals 2 and 3 and electrically connect them, the current entering,for example, through the upper stud 4 to terminal 2, through bridgingmember 6 to terminal 3, and out by 1ts stud 4 and thence by connector 7to stud 8 which may be connected to the winding of an overload trippingcoil, here omitted for the sake of The bridging member 6 iscarried bybut insulated from the arm 9 pivoted in the bracket or housing10 at 11.As means foroperatin'g the arm 9 and for cramping the laminated member 6against the terminals 2 and 3, are provided the links 12 and 13 pivotedto each other at 14; and the link 12 is pivoted to the arm 9 at 15,while the link 13 is pivoted in the housing or bracket 10 at 16. Thelinks 12 and 13 form a toggle which is under set in the full circuitclosing position asshownin Fig. 1. The link 13 extends outwardly beyondthe pivot- 16 to form an operating lever 17 provided with the hand grip18. A spiral spring 19, un-. der tension in the position shown, isconnected at one end at 20 to the arm 9 and at itsother end at 21 to thehousing or frame 10. And a spiral spring 22, under tension in theposition shown, is connected at one end at 21 and at its other end at 23to the toggle link'13. At 24 on the operating lever 17 is pivoted aroller 25 with which? engages the latch 26 pivotedat 27 upon the frameor housing 10. The latch \26 has a rearward extension 28 to which ispivoted at 29 the vertically extending rod or pin 30. The pin 30 extendsinto the path of travel of the armature 31 pivoted .at 32 and adapted tonormally rest upon the nonmagnetic stop 33 between the cores 34 and 35of two electromagnets whose coils are 36 and 37, respectively. A thirdelectromag' net'has the coil or winding 38 andthe core 39 pivotallymounted. and magnetically cross connecting the two. similar armatures31, only one of which is visible in Fig. 1. The usual overload trippingc011, not

shunt carbon, 40, pivoted at 4:1, and in elec trical communication withthe intermediate metallic shunt contact 42, both the carbon and contact42 being in permanent; electrical communication with the lower terminalblock 3 through the conductor 43.

The carbon 40 cotiperates with. the stationary carbon 44 pivoted at 45'on the bracket 46 mounted on and in electrical communicationwiththemain terminal 2. The bracket 46 carries also the stationaryintermediate shunt contact 47 with which the shunt contact 42 engages.

Referring to Fig. 2, A, B andC are the conductors of a three wiresystem,B being the neutral wire. The dynamo-electric machines, as generators, Dand E are connected in series between the conductors A and C, and theneutral conductor Bis connected between the machines D and E. A thirdmachine or generator F, of voltage equal to the sum of the voltages of Dand E, may be employed and connected as shown. In the conductors A and Care connected circuit breakers G and H, respectively, such, for example,as shown in Fig. 1, andhere shown diagrammatically by the main terminals2 and 3, the laminated bridging member 6 and the three potential coilsoperating to control the armature 31. Thecoils 37 and 38 are connectedin parallel with each other across the conductors-A and B in the caseof-the circuit breaker G in Fig. 2, while the coil 36 is connectedbetween the neutral B and the conductor C of the other circuit of thethree wire system. These windings are so disposed upon their cores that"the coils 36 and-37 produce ma etism in the same direction, as indicatedy the two curved arrows in Fig. 1.' When a balance of voltage exists onthe three wire "system, that is, when the voltage between A and B isequal to or bears a proper relation to the voltage between 'B and C, themile 36 and 37 are balanced in their efiectupon the armature 31 and thesame remains at rest. If, however, the voltage between B and C falls orif the voltage between A and B increases, the armature 31 of the circuitbreaker G will be drawn upwardly and will strike the pin 30 to'tilt thelatch 26 to unlock thecircuit breaker with the result, as wellunderstood in the art, of causing or allowing the toggle 12, 13 tocollapse, with resultant movement of laminated bridging member 6 awayfrom the terminals 2 and 3, to break circuit. And

as well understood in the art, the intermediate shunt contact 42 leavesits companion 47 shortly after the member 6 hasseparated from terminals2 and 3, and finally carbon 40 separates from carbon 44, the final arctaking place between these carbons without danger to the maincontacts,the circuit being'then completely ruptured. The coil 38 is not essentialto the operation of the apparatus as just described, but its presenceincreases the sensitiveness. of the instrument, so that it will respondto smaller variations of voltage. And the situation is the same asregards circuit breaker H, that is, when the voltage between A and Bfalls, or the voltage between B and G increases, it is tripped by itsarmature 31.

Considering the magnetism produced by the coils 36,37 and 38,coil 38operates cumulatively with coil 37 to produce magnet-ism through thearmature 31, and coil 38 operates cumulatively with the. coil 36 inproducing-magnetism through the armature 31,

as indicated by the arrows in Fig. "1. Coils 36 and 37 however, bothproduce magnetism in the same direction through the armature 31, and areopposed in their effects upon the armature 31, one coil, as 36, exertinga force in one direction upon the armature 31, while the other coil, 37exerts a force in opposite direction upon the arma ture. That is, bothcoils 36 and 37, attract the armature 31, and since they are disposedvon opposite sides of the armature 31, their attractive forces onarmature 31 are 0 posed. When, however, the magnetizing e ect of thecoil 36 diminishes, or when the magnetizing effect of coil 37 increases,coil 37 gains control of the armature 31 and thereafter ing control ofthe armature, by a relatively small preponderance in ampere turns, thearmature 31 is thereafter acted on with great force sufficient to tripthe breaker. This is distinguished from the case Where coilsdifferentially acting upon a core aree nployed, for in the latter case,when onefiibil pre ponderates over the other, there is available onlythe difference of their ampere turns and this is necessarily small froma practical.

standpoint, and insufficient-for performing the work required in thesystem here disclosed for direct actuation of the tripping mechanism.

The circuit breakers G-and H may have their tripping mechanisms suitablymechanically interconnected, as, for example, by means shown in U. S.Patents No. 746,587, No. 7 54,505, or No. 825,144, so that. upon theelec trical tripping of either one, both are tripped. This may beaccomplished by an arrangement such as shown in Fig. 3 where twoautomatic circuit breakers are shown in front elevation. They have theirtripping latches 26, 26 mechanically connected by a rod or connector 48,whereby when the tripping mechanism of either circuit breaker isenergized or v operated, both breakers are tripped. 7

While I have shown my invention" as adapted to a three wire system, itis to be understood that the same may be applied to systems of greaternumber of conductors or, in fact, in an relation where a relativefluctuation of v0 tage between two circuits is to be followed by theinterruption of one or the other, or both, of such clrcuits.

This application is a division from my application Serial No..353,04=7,filed January What I claim is: 1. In combination with an electricdistribution. system comprising a plurality of conductors all normallyat different potentials with respect to'each other, of a circuit breakerincluded in one of said conductors,

means restraining said circuit breaker in normal position, a movablemagnetizable mass for actuating said restraining means, potential coilsexerting forces in opposed directions upon said movable magnetizablemass, one of said coils subjectedto the potential between the conductorin which said circuit breaker is included and another cons ductor ofsaid system, and another of said coils subjected to the potentialbetweeen two conductors of said system other than the conductorincluding said circuit breaker, and a stop preventing movement of saidmagnetizable mass toward a pole of one of said potential coils. I

2. In combination, a plurality of circuits,

a circuit breaker connected in each circuit,

3. .An automatic circuit breakercomprising a movable contact member,means for restraining said contact member in normal position, and'meansfor actuating said restraining means comprising a movable magnetizablf'emember, coils exerting forces in opposite directions upon saidmagnetizable member, one of said coils traversed by currentfrom thecircuit in which said movable contact member is connected, another ofsaid coils traversed by current from a differnetizable member, andpotential coils exerting forces in opposite directions upon saidmagnet-lzable member, one of said coils subjected to the potential ofthe circuit in which said movable contact member is connected, anotherof said coils subjected to the potential of a different circuit, and astop limiting the approach of said magnetizable-member toward a pole ofone ofsaid coils.

5. In combination, a plurality of circuits,

a circuit breaker included in one of said circuits and comprising amovable contact member and means for restraining the same in normalposition, tripping mechanism for said circuit breaker comprising amovable magnetizable mass and coils having poles disposed upon oppositesides of said magnetizable mass and exerting forces on said magnetizablemass in opposite directions, one coil traversed by current from thecircuit in which said circuit breaker is connected, another coiltraversed by current from another circuit, and a stop for saidmagnetizable mass for insuring movement of said mass toward the polewhich gains control over said magnetizable mass.

' 6. In a three or more wire system, a circuit breaker connected in eachof a plurality of the inter-related circuits, and tripping mechanism foreach circuit breaker comprising a movable magnetizablemass and opposedpotential coil-s,,one of said potential coils connected between theconductor in which said circuit breaker is. connected and anotherconductor, another of said coils connected between said other conductorand a third conductor, and means interconnecting the tripping mechanismsof the different circuit breakers.

7 An automatic circuit breaker comprising a movable contact member,means. for restraining said contact member in normal position, andtripping mechanism for said breaker comprising a movable magnetizablemass and a plurality'of potential coils,'two of said coils coiiperatingin their action upon said magnetizable mass and connected across a pairof conductors, and a third potential coil exerting force on saidmagnetizable mass in opposite direction to said potential coils andconnected across other conductors.

8. An automatic circuit breaker comprising a movable contact member,means for restraining said contact member in normal position, andtripping mechanism comprising a pivoted armature and a plurality oilmagnetizing coils therefor, one of said coils being a potential coilconnected across a pair of conductors, another of said coils being apotential coil connected across other conductors and exerting force onsaid arma ture in opposite direction to -said first mentioned potentialcoil, and a third coil ('20- operating with said second potential coil.

9. Electro-magnet-ic tripping. means'for a circuit breaker comprising anarmature, opposed poles acting uponsaid armature, p'0' tentialcoilsconnected in different circuits magnetizing said poles, and a thirdcoil opera ting cumulatively with one of said potential coils upon saidarmature. I

10. Electro-magnetic tripping machanism for acircuit breaker comprisinga pivoted armature, a magnetizing coil associated therewith at thepivotal axis thereof, a potential coil connected across a pair ofconductors operating cumulatively with said first mentioned coil uponsaid armature, and

a second potential 0011 connected across different'conductorsopposing-said first mentionedpotential coil.

, 11. An automatic circuit breaker comprising a movable contact'member,meansLfor restraining said contact member in normalposition, andtripping mechanism comprising an armature and a plurality of poten tialcoils operating thereon, two of said potential coils connected inparallel with each other across a pair ofconductors, and a thirdpotential coil connected across other conductors and magnetizing said-armature cumulatively with said first mentioned coils, said thirdpotential coil exertin force on said armature in opposite direction tothe force exerted thereon by, one of said first mentioned potentialcoils.

12. An automatlc c1rcu1t breaker comprismg a movable contactmember,means for restraining the same in normal position, and

tripping mechanism comprising an armature and a plurality of potentialcoils operating' thereon, two of said potential coils connected inparallel with each; other across a pair of conductors, and a thirdpotential coil connected across other conductors and exerting a .forceon said armature in a direction opposite to a force exerted thereon byone of said first mentioned coils.

'13. In a three or more wire system, neutral and outside conductors, acircuit breaker connected in an outside conductor, tripping mechanismtherefor comprising a latchactuating armature, potential coils formagnetizing said armature, two of said potential coils connected .inparallel across a neutral conductor and an outside conductor, andanother potential coil connected. across said neutral conductor andanother outside conductor and normally magnetizing said armaturecumulatively with said two potential coils.

acting'upon said armature, coils traversed by current from diflerentcircuits magnet1zing said poles, and a third coil magnetizing the axialportion of said armature.

16. Electro-magnetic tripping mechanism comprising an armature having avibrating portion andanaxial portion, opposed poles acting upon thevibrating portion of said armature, potential coils connectedindifferent circuits magnetizing said poles, and a third coilmagnetizing the axial portion of said larmature.

17. Electro-magnetic tripping mechanism comprising an armature having avibrating portion and an axial portion, opposed poles acting upon thevibrating portion of said armature, potential coils connected indiffer-v ent circuits magnetizing said poles, and a third coil operatingcumulatively with said" potential coils and disposed about the axialportion of said armature.

18. An automatic circuit breaker comprising a movable contact member,means for restraining said contact member in normal position, trippingmechanism for said circuit breaker comprising a movable magnetizablemass and a plurality of magnetizing coils, two of said coils cooperatingin their action upon said magnetizable mass and traversed by currentflowing between a pair of conductors, and a third coil exerting a forceon said magnetizable mass in opposite direction to a force exertedthereon by one of said coils and traversed-by current flowing betweenother conductors.

19. An automatic circuit breaker compris ing a movable contact member,means for restraining said contact member in normal.

- ing traversed by current flowing between a pair of conductors, anotherof said coils traversed by current flowing between other conductors. andexerting force upon said armature in opposite direction, and a thirdcoil coiiperatingwith said second coil.

20. In a system comprising a plurality of circuits, a circuit breakerconnected in each of a plurality of the inter-related circuits,

and tripping mechanism for-each circuit breaker comprising a movablemagnetizable mass and magnetizing coils acting in opposite directionsthereon, one of said coils traversed by current flowing between thecircuit, the tripping mechanism of each circuit breaker comprisingmagnetizing coils,- one coil traversed by current flowing in the circuitin which its circuit breaker is connected, another coil traversed bycurrent flowing in the circuit in which another circuit breaker isconnected, and mea'ns for interconnectin the tripping mechanisms of all.the circuit reakers.

22. In combination, a plurality of circuits, a circuit breaker connectedin each circuit, the tripping mechanism of each circuit breakercomprising a plurality of magnetizing coils traversed by current of thecircuit in which their circuit breaker is connected, another coilassociated with said coils and traversed by current of a circuit inwhich another circuit breaker is connected, and means forinterconnecting the tripping mechanisms of all the circuit breakers.

23. In combination, a plurality of circuits, a circuit breaker connectedin each circuit, the tripping mechanism of each circuit comprisingmagnetizing 'COllS traversed by current from the circuit in .which theircircuit breaker is connected, another coil traversed by current from acircuit in which another .circuit breaker is connected and exerting aforce in opposition to one of said coils, and means for interconnectingthe tripping mechanisms of all the circuit breakers. 1

24. In combination, a plurality of circuits, a circuit breaker connectedin each circuit, the tripping mechanism of each circuit breakercomprising'a pair of potential .coils connected in parallel across thecircuit in which their circuit breaker is connected, a third coilsubjected to the potential of the circuit in which another circuitbreaker is connected and exerting a force in opposition to one of saidcoils, and means for interconnecting the tripping mecha nisms of all thecircuit breakers.

2 5. The'combination with a movable contact member of a switch'orcircuit breaker, of means for restraining the same in normal position amag'netizable member for actuating said restraining means, poles actingin opposite directions upon said magnetizable member, a magnetizing coilfor one of said poles traversed by current from the circuit in whichsaid movable contact member is connected, another coil magnetizinganother of said poles and traversed by current from another circuit, anda stop limiting the movement of said magnetizable member toward one ofsaid poles.

26,. Electro-magnetic tripping means comprising an armature, poles onopposite sides of said armature exerting forces in opposite directionsthereon, coils connected in different circuits magnetizing said poles,and a third coil operating cumulatively with said first mentioned coilsin magnetizing said armature;

27 Electro-magnetic tripping means comprising an armature, poles onopposite sides ofsaid armature exerting forces in opposite directionsthereon, potential coils connected in difierent circuits magnetizingsaid poles, and a thirdpotential coil operating cumula tively with saidfirst mentioned coils in magnetizing said armature.

28. Electro-magnetic tripping mechanism comprising an armature, polesacting thereon in opposite directions, one of said poles normallypreventing the approach of said armature toward a second of said poles,magnetizing coils for said poles connected respectively in differentcircuits, and a third coil augmenting the attraction upon said armaturewhen said second pole has gained control thereof.

29. Electro-magnetic tripping ,mechanism' comprising an armature, polesacting in opposite directions upon said armature, a coil formagnetizingone of said poles connected in one circuit, a coil formagnetizing another pole connected in another circuit, a stop limitingthe approach of said armature toward one of said poles, and a third coilaugmenting the attraction of said armature toward a second of said poleswhen said sec- 7 0nd pole has gained control of said ar; mature. 7

30. Electro-magnetic tripping mechanism comprising an armature, a stopagainst which said armature normally rests, poles acting in oppositedirections upon said armature, magnetizing coils for said polesconnected respectively in diiferent circuits and a third coil assistingin the movement of said armature after it has left said stop.

In testimony whereof I have hereunto affixed my signature in thepresence of the two subscribing witnesses.

WILLIAM M. SCOTT.

Witnesses:

ELEANOR .'I. MCCALL, A. STEINBOCK.

